title: Explaining the increasing heritability of cognitive ability across development: a meta-analysis of longitudinal twin and adoption studies.
abstract: Genes account for increasing proportions of variation in cognitive ability across development, but the mechanisms underlying these increases remain unclear. We conducted a meta-analysis of longitudinal behavioral genetic studies spanning infancy to adolescence. We identified relevant data from 16 articles with 11 unique samples containing a total of 11,500 twin and sibling pairs who were all reared together and measured at least twice between the ages of 6 months and 18 years. Longitudinal behavioral genetic models were used to estimate the extent to which early genetic influences on cognition were amplified over time and the extent to which innovative genetic influences arose with time. Results indicated that in early childhood, innovative genetic influences predominate but that innovation quickly diminishes, and amplified influences account for increasing heritability following age 8 years.
authors.affiliation: Department of Psychology and Population Research Center, University of Texas at Austin.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Briley
authors.forename: Elliot M
authors.initials: EM
authors.lastname: Tucker-Drob
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology*; D000300:Adoption; D000367:Age Factors; D002648:Child; D002652:Child Behavior / Q000502:physiology*; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D035781:Siblings; D014427:Twins / Q000235:genetics* / Q000706:statistics & numerical data
keywords: amplification; behavior genetics; childhood development; cognition; cognitive ability; development; intelligence